Metformin: Harmful or Helpful to Your Gut Bacteria?

Metformin is one of the most widely prescribed drugs across the globe. It is well established that one of the most common side-effects of metformin is stomach troubles–more specifically loose stools and a frequent urge to use the bathroom.

With its impact on your digestive system, it’s important to ask: us this wonder drug helping or harming the bacteria in your gut?

Surprisingly, research has found that metformin actually increases the good bacteria in your gut, explains HealthDay News: “Metformin appears to trigger favorable changes in intestinal bacteria, according to a study published online Dec. 2 in Nature.”

In a study with 784 participants with and without type 2 diabetes from China, Denmark, and Sweden, the results clearly revealed that metformin positively effects the bacteria in the gut by improving the bacteria’s ability to produce short-chain fatty acids. These fatty-acids are well-known for their ability to lower blood glucose levels.

“The researchers also found that patients who take metformin have more coliform bacteria in their intestines, which may explain why the drug causes side effects such as bloating and increased flatulence,” explains HealthDay News.

How do these results compare to other oral medications used in treating type 2 diabetes? So far, no other diabetes drug demonstrates a similar impact or any impact at all on improving gut bacteria.

The study also concluded something very telling about the link between type 2 diabetes and gut bacteria overall:

“When studying type 2 diabetes patients not being treated with metformin, we did, however, discover that they — irrespective of whether they were from Denmark, China or Sweden — had fewer of the bacteria which produce the health-promoting short-chain fatty acids,” explains senior author Oluf Borbye Pedersen, M.D., a professor with the Center for Basic Metabolic Research at the University of Copenhagen in Denmark.

“Whether the lack of certain combinations of fatty acid-producing intestinal bacterial species is one of the factors contributing to type 2 diabetes is currently being investigated.”

Aside from the side-effects, did you experience positive results in your blood sugar levels while taking metformin? It just might have something to do with your gut!

Comments

Found out I’m diabetic late May of this year, 2015. A1c was 10.7%, glucose was 454. I requested to try pills first. Given Metformin and by Sept my A1c was 6.2% and avg glucose 143. For my age glucose can be 145 before meals and 180 at bedtime. My 2nd A1c just done the 15th of Dec was still 6.2% and have dropped from 2,000 (2 tablets) a day to 1/2 a tablet twice a day or 1000mg. Have also changed not so much what I eat but how much I eat. Can have up to 45 carbs per meal and 15 to 20 carbs for a snack. Due to this I have also lost 35 lbs since early June. I don’t deprive myself of things I like, just have them in smaller amounts. Such as instead of a “bowl” of ice cream with lots of topping, only 1/2 c with 1 teaspoon of topping. Chips I count out to 1/2 of a serving, For a 12″ pizza 2 slices or 1/4 instead of 1/2 or more. Started out using a digital kitchen scale and measuring cups and spoons, now unless something new I know pretty much what a serving is. Not that hard to do and well worth the time.

I’m type 2, and 65 years old. I’ve had a very hard time finding a medication that I can tolerate. I’m currently on Glimepiride, 2 mg in the morning and 2 mg at night. I tried Metformin, but it gave me constant diarhea, and I’ve been told that most of the meds for diabetes will cause this. Any suggestions for helping the stomach/intestinal troubles these meds can cause?

Hi Christy…I am 59 type 2 diabetic…was diagnosed in 2010…Dr put me on metformin took it for 4 yrs and it gave me really bad diarrhea, everyday, after husband and I moved had to get a new Dr. spoke to her about all my side affects and she changed me asap to Glimepiride, 1 mg plus an injection, victoza, .6 mg and it has lowered my blood sugar to almost normal to pre-diabete readings.

Hi, I took metformin for two years and found that it had a depressive effect and made me quite vague. As soon as I stopped taking it, within 24 hours, I felt revitalised, so much better. I tried to push through- to see if these side effects would go away but they didn’t. I literally can’t take it- it even makes me drowsy when I drive.

My husband had good results with Metformin and no side effects but after a few years started having kidney problems and the doctor said to come off Metformin for this reason.This was a few years ago. Kidney readings have improved. He’s 80, been type two since age 64.

i had alot of trouble when i first took it . running to the bathroom only lasted 2 weeks i stopped it for so much pain in my belly, then tried it again this year, same i quit for 2 weeks back on it now they only bad now i need to take a fiber 3 times a day plus laxative at bed , chronic of no b.m. but i am keeping my sugar at 88-110 ,which i do feel better and losing weight but not on the scales

I am a Type 1 Diabetic and my Endocronologist just put me on Metformin. I have been taken 6-8 cc of Humalog 3 times a day for about 2 1/2 years. I now take just 2 cc before Breakfast and Dinner along with 1000mg of Metformin. I still take 10cc of Lantus at night. I have been on Metformin for about 10 days and my blood sugars have been just fine.

I’m happy it’s working for you Ronald. I’m obvioulsy no doctor, but from what I understand of the mechanisms of metformin, combined with insulin there would be higher risk for hypoglycemic lows. When I fwas taking metformin, hypoglycemia was a regular thing during my treadmill workouts.

Sounds like your Doc has you dialed in well 🙂 Best of luck and Happy Holidays!

I can attest that Metformin has caused loose bowel movements and lots of flatulence. My wife is a nurse of 23 years and has noted this side effect and has come to the conclusion as such. T2 for 10years.

Metformin litterally tears me up to the point that I can only take half my evening dosage or else wear a diaper….lol. seriously, though it does control my sugar and I have been taking it for over 5 years

I had to switch from the regular Metformin to the Extended Release, as the other type was giving me debilitating diarherra. I am also a Chron’s patient who has had part of my colon removed, the ascending colon which is the part of the colon that removes water from the waste. So I already had challenges with that, so my doc changed me over. It seems to work fairly well, however my fasting a.m. blood sugars are in the 120s consistently.

I am very early T2. I have been on Metformin ER 500 mg each evening for over a month (and should have started sooner, when I was prediabetic). I’m sorry it hasn’t worked for some of you out there. For me it has been a godsend.I have had no gastric problems whatsoever! The Metformin extended release is supposed to be gentler than the rapid acting kind. Also, sometimes side effects have to do with which generic version your pharmacy uses. The brand name (Glucophage XR) could be better for some people. Also, for some who have gastric side effects, it might be beneficial to start with a lower dose and give the med a little more than 2 weeks to give the body time to adjust., and bring you dose up gradually, depending on your weight. I take 500mg in the evening and my morning fasting blood sugars run between 76 and 91. I also make a point to walk 20 minutes after I finish the supper dishes, average over 10,000 steps a day, use the bowflex 2-3 times a week, and hold my carbs to about 30 grams per meal. By doing this I can keep my post prandial blood sugars below 130-140. If I have a snack, it’s a very low carb snack, like nuts. I make sure I get plenty of fiber and drink plenty of fluids. Metformin doesn’t work by itself. Diet and exercise must be included for maximum benefits. I am using everything in my arsenal to keep my blood sugars in the target range I have set for myself. If my blood sugars start inching up to where I don’t want them, I will decrease the carbs at meals and add on insulin in a New York minute to get them in range!!! I want to avoid complications, as we all do.

Metformin took my hair out. Prior to taking this medication I had a full head of hair. I took this medication for a year and by the time I realized the medication I had lost just about all of my hair in the crown of my head. When I stopped taking this medication my hair began to grow back.

I can’t take the two metformin a day my doc wants me on. 1 helps my BS a lot, mild diarrhea, 2 sends me to the Imodium bottle. They say the side effects go away, but I’m not having any luck. I take probiotics and eat right. Anyone else have suggestions?

Yes… Berberine instead of Metformin, about 10 minutes before each meal… Also, build-up your gut flora. What I’m using for the build-up (everybody’s different) is The Brinery Seasonal KimChi, or Farmhouse Culture KimChi (although making your own, would probably be better economically). Increase intake of fluids and fiber throughout the day… So far, this is what I’m learning to be CRITICAL, just for STARTERS. Since I had BS’s at 10, end of September… Now, still driving them down, but at a more manageable 5.1, WITHOUT ANY diabetic medication. I didn’t see ANY progress till I made the changes/adds, mentioned above. I do log daily… experimenting/monitoring, as changes are being made. Again, everyone’s different and as a medically “diagnosed” T2D, I can only verify what is working for me. Since I believe that the “medication” that was “prescribed for me”, was NOT for me, just my T2D profile. So I decided NOT to take ANY (or start) “medication” addressing the current common metabolic syndrome symptom(s), that the doc/tests have clearly shown. Instead, focusing on the root-cause, rather than picking-off a symptom, or set of symptoms. Skeptical of modern medicine or doctors, you ask? No… Not at all. Just never did like profiles, or being profiled (especially since I believe in, garbage in-garbage out). So since my doctor has been monitoring my progress, congratulating me on how everything “appears” to be coming down (still needs some work, he says, but coming down nicely)… The weight, the bp, the bs, the fatigue, the brain fog, the feet pain, the feet numbness, the constipation, the lack of energy to do simple walks, the depression, etc… All adds up to ONE MAJOR PROBLEM… That is… He never once asked me if I’ve been taking any or all of the medications that he prescribed to my profile (I mean, me…) He continues to assume, which at this point I prefer it that way! Why? Because I want him to be as convinced (beyond MY reasonable doubt) as possible, that what I’m doing is to have him and his major hospital/medical system protocols, prove to me that the AMA, ADA, AHA way, is the way! I’m simply NOT trying to be stubborn, or at worst, be totally ignorant or stupid… Or a rebel without a cause! I’ve clearly allowed the doctor to present his facts, as it pertains to me. I’ve done everything he’s asked me to do (along with initially advising him that I don’t currently TAKE ANY medications period, not even aspirin unnecessarily, now you’ve given me scripts for 6 drugs, just for starters, according to the T2D-Profile, that I’ve been profiled into, and he’s NOT unique in this approach). So, I think I’m way overdue from wrapping up here (yeah, right:)… When I started this Reply, I want to make clear that the “suggestions” that I made, is NOT take those things AND GOODBYE T2D!! No, not at all. I just wasn’t seeing anything moving till I did those things… Believe me, I filled those scripts… Still have them on the table… Unopened… Looking at my logs… I can’t start those symptom scripts… They are NOT for me… They are for Joe “T2D-Profile” Public… Until all those tests that they are taking to “monitor MY PROGRESS” start to say that the MEDICATIONS ARE NOT WORKING any more… I will continue to follow “their advice” my way… which is I am NOT taking anything they give me, period. Why? Because your tests say so!

My doctor, not to mention all the literature, to try and get near 100, so I don’t have damage from high blood sugar. I exercise regularly, but am a bit limited by a disability. Nothing I do, not even strict Atkins phase 1, gets me that low. Metformin worked, but can’t live with the constant diarrhea. Wonder how much was that vs the medication.

I am T2 and have been taking several medications for 3 years now, including Metformin and insulin. My doctor has increased my Metformin dosage to 1,000 mg a day now. I find it very helpful, but I had such stomach pains! On my own I split my dosage to 500 mg at breakfast and 500 mg at dinner. That has helped greatly! No more stomach pains. The key is to split your dosage if you have to take multiple pills and to always take with a meal. My doctor was all for my splitting the dosage.

Merry Christmas, Ginger, and Season’s Greeting to my other comrades in diabetes self-care, healthcare management and diabetic interest in general.

In January of 2014, I was admitted to Binghamton General Hospital due to some wintertime depression I was experiencing due to Seasonal Affect Disorder (Depression), Nicotine Addiction and Unmanageable Diabetes. While admitted to the hospital I reunited with one of my first Endocrinologists Dr. Ramanujen, as very respected and hardworking diabetes healthcare worker. He prescribed Metformin as an agent for helping me better control my blood sugars. The effects we almost immediate, bringing my blood sugars down from the 2 and 300’s into normal range. Unfortunately, with the introduction of the drug I did experience some terrible stomach irritation and discomfort. After lowering the dose of metformin I could handle, until I was able to ‘stomach the pain,’ pun intended, I was able to again increase the dose to its most effective, recommended level. I believe Metformin does good things for my body and blood sugar management and am grateful for the drug. I have also read that metformin increases longevity, something else I am grateful for as I am able to enjoy my life as a diabetic far more now that I ever was without the drug.

Best of luck to all of you, and never give up hope toward better living with diabetes and the best of faith toward greater solutions for the years to come!

I cant handle Metformin I am running to the bathroom every 5 minutes. I use cinnamon pills I take two in the morning and two in the evening. And if I am feeling off I will take one between the two in the morning and evening.

I had a problem when I first started metformin 18 yrs past. I am t2 since my 40th bd 29 yrs. ago. this medicine highly suggest it be taken with food. believe me that was the only way it worked for me. I was recently diagonosed with onset of kidney desease .; don’t know yet if there is a correlation.; waiting for next labs.

I was on metformin and it’s attendant weight gains, for years for insulin resistance and PCOS then I went through menopause and could go off of it. I did for over 5 years with no problems. My A1-C’s were always near the high end of normal, but nothing to worry about. Then, due to another issue, I was put on prednisone for a week. A month later, in for my check up, including blood work and my A1-C is at 8.3. My dr. immediately put me back on metformin and I immediately gained 58lbs in 2 months while eating a “diabetic diet” which did not impact my blood sugar levels at all. Now what? She wants me on one of these new non-insulin things, somehow I get to choose?, and I’m not going near something that antagonizes the pancreas that puts out the insulin my body already doesn’t like. Has anyone else been triggered into excessive weight gain and sugar levels with metformin?

Metformin by itself tends to lower blood sugars and weight gain most people. Your problems with high blood glucose and weight gain could be due to another medication you may have started around the same time. Prednisone is one med that will certainly increase blood sugars and weight! A GLP-1RA combined with a long-acting insulin could be very helpful for you.

No problem with t he metformin, except the b12 being too low and I’m always tired. Taking extra b12 does help. But I have to be very careful with over the counter pain relievers. Taken to often causes seizures.